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Old 05-21-2015, 01:31 PM   #6 (permalink)
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gueff - '19 Mercedes Benz A250 4MATIC AMG
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Originally Posted by Daox View Post
I think variable lean-ness is ideal. You want your throttle open for lower pumping losses, and if you can adjust power output via AFR, you got what you want (aka a gasoline diesel basically).

Sorry, I have no idea on the timing. A dyno sounds like its really your best bet. Unless you get some instrumentation, thats going to be hard to figure out on the road.
I do have instrumentation. I can log cylinder filling in grams of air per revolution. Leaning afr past ~15.5 drops it quite a bit. It does not seem however that the extra timing does make up for it. Perhaps I have already exceeded MBT.
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